Map of Turkey
Earthquake is a disaster known as violent shakes due to the movement between tectonic plates in the earth’s crust. (World Health Organization n.d.).
Turkey is listed as one of the top ten countries that experiences earthquakes regularly due to its location that is close to the major fault lines (WorldAtlas n.d.).
Understanding the nature of earthquakes in Turkey is important to scientists, policy makers and people in the country itself, in order for them to be prepared and thus make the right policies that can benefit the people.
Due to this, studies about earthquakes in general have a lot of benefits such as:
Through this study, not only Turkey, but countries all around the world can improve their technologies, become more knowledgeable about earthquakes and help to mitigate risks, as well as enhance to more efficient disaster management strategies.
The “Turkey Earthquakes (1915-2021)” data set utilised in this study was obtained from Kaggle, in which it comprises of all the earthquakes with a magnitude greater than 3.5 that took place in Turkey and nearest areas from 1915 to January 2021.
The main source of the data is from the Kandilli Observatory and Earthquake Research Institute (KOERI), which specialises in the research of earthquakes.
The data set contains 15 variables, as explained in the table below. However, not all of the variables are utilised in this study, as they are chosen according to the analysis to be carried out.
This study has three main objectives as follows:
Bar plot has been used to identify the trend of frequency of earthquake over time. Based on the plot:
13 events of earthquakes that have frequency that ranged from 1-9
Highest frequency was in 2020 with 934 events recorded.
6 events of earthquakes that have frequency more than 500 which was in year 1999, 2005, 2011, 2012, 2017, and 2020.
Area plot has been used to identify the trend of average magnitude and average depth of earthquake over time. Based on the plot:
The highest average magnitude was in 1942, where the average magnitude was approximately 5.65 with an average depth of 26.13km.
The lowest average magnitude occurred in 2009, with a magnitude of 3.72 and a depth of 14.09km.
The light earthquake intensity where the magnitude is less than or equal to 4.9 spans from 1960 to 2021, displaying a range of average magnitudes from 4.45 to 4.83 and depths from 19.20 to 45.11 km.
The moderate earthquake intensity with magnitudes greater than 4.9 and less than or equal to 5.9 covers years from 1915 to 1963, exhibiting average magnitudes from 4.92 to 5.65 and depths from 9.33km to 62.50km.
Scatter plot has been used to identify relationship between frequency and average magnitude of the earthquake. Based on the plot:
The correlation coefficient between the frequency and average magnitude of earthquakes is -0.7805606, indicating a negative correlation.
As the frequency of earthquakes increases, the average magnitude tends to decrease, and vice versa. This has been supported by previous study as well.
The word cloud visualises the earthquake frequencies in different locations of Turkey and its neighbouring countries.
-The larger the word, the higher the frequency of earthquakes in that location.
-Out of the 95 locations in the dataset, nine places are outside of Turkey, including Ege Denizi (Aegean Sea), Suriye (Syria), Gurcistan (Georgia), Irak (Iraq), Iran, Ermenistan (Armenia), Kibris (Cyprus), and Azerbaycan (Azerbaijan). The remaining locations belong to Turkey.
-Earthquakes occur more frequently in Akdeniz, Manisa, Mugla, Van, Kuthaya, Kahramanmaras, Denizi, Elazig, Burdur, Ankara, Bingol, Balikesir, Malatya, Izmir, Erzurum, and Canakkale.
-Akdeniz has the highest earthquake frequency.
-Ege Denizi (Aegean Sea) is the second-highest earthquake frequency.
-The word cloud does not provide information about the magnitudes of the earthquakes.
-However, Turkey and its neighbouring countries are situated in seismically active regions, where earthquakes of various magnitudes can occur.
-Therefore, it is crucial to visualise the earthquake clusters based on their magnitudes to gain a more comprehensive understanding of the seismic activity.
-The magnitude of an earthquake is measured on the Richter magnitude scale, which is a logarithmic scale used to gauge the amplitude of seismic waves generated by the earthquake.
-Here are the categories of earthquakes based on their magnitudes (The Associated Press 2012):
The earthquake clusters are visualised through an interactive map.
-Three earthquake clusters.
-The left circle has the greatest number of earthquake events.
Located on the Eurasian plate, the African plate, the Aegean Sea plate, and the North Anatolian Fault Line (NAF) (Earthquake Hazards Program 2023).
The movement between the Eurasian and African plates is against each other, exerting pressure on each other (Demirci 2023).
The NAF line is one of the fastest-moving and most active right-lateral strike faults in the world (Demirci 2023).
It is 1400 km long and runs from the east of Turkey to the west of Turkey and ends at the Aegean Sea (Comfort et al. 2023).
Provinces and cities included Gallipoli, Marmara Sea, the Gulf of Izmit, Adapazarı, Duzce-Bolu, Gerede, Merzifon, Suluova and Erbaa, Niksar, Kelkit Valley, Erzincan, Erzurum, Varto, Van, Canakkale, Edremit, Bursa and Iznik (Demirci 2023).
-The central circle has the least earthquake events, with a 988 number of earthquake events.
-The right circle recorded 6992 earthquake events.
Located on the Eurasian plate, the Arabian plate, and the East Anatolian Fault Line (EAF) (Earthquake Hazards Program 2023).
The opposing movements of the Eurasian and Arabian plates create intense stress, increasing the likelihood of earthquakes (Demirci 2023).
The EAF, a strike-slip fault line located in eastern Turkey, further contributes to seismic activity (Demirci 2023).
Approximately 1000 km long and runs diagonally across Hatay, Osmaniye, Gaziantep, Kahramanmaras, Adiyaman, Elazıg, Bingol, Mus, Erzincan, and to the NorthAnatolian Fault Line (Comfort et al. 2023 and Demirci 2023).
The interactive map visualises the selected top 30 earthquakes based on magnitude, with the colour of the circles representing the magnitude.
-The darkest-coloured circle indicates the largest earthquake magnitude recorded in Turkey, measuring 7.9 on the Richter scale, which occurred in Erzincan.
-The second-greatest magnitude, measuring 7.7, is occurred in Gaziantep and Akdeniz.
-The third-greatest magnitude in Turkey is 7.6, recorded in Kahramanmaras and Turkiye.
The gif animated scatterplot visualises the distribution of the earthquakes based on magnitude over time for the top 10 locations. -The top 10 locations are Akdeniz, Denizli, Ege Denizi, Izmir, Kahramanmaras, Kuthaya, Malatya, Manisa, Mugla, and Van.
In 1926, Akdeniz experienced a powerful earthquake with a magnitude of 7.7.
In 1948 and 1957, Akdeniz measured two earthquakes with magnitudes 7.2 and 7.1 respectively.
In 1970, Kuthaya registered a magnitude of 7.0.
In 1976, Van encountered a strong earthquake with a magnitude of 7.5.
In 2011, Van experienced another earthquake with a magnitude of 7.2.
In February 2023, Kahramanmaras experienced a earthquake with a magnitude of 7.6.
Death toll surpassing 50000 people, particularly 45968 confirmed deaths in Turkey and 7259 confirmed deaths in Syria (ReliefWeb 2023).
-Once an earthquake of at least 7.0 magnitude occurs, the subsequent earthquake events exhibit reduced magnitudes below 6.
-This decline in magnitude signifies the release of stored energy from the previous seismic event.
Normal Fault
Body-wave and Surface Magnitudes
A correlogram of the magnitude types is simply a visual representation of the correlation matrix.
Non-significant correlation
Highest correlation
Negative correlation
These connections can help with further research and interpretation of the data, such as finding out what causes the correlations and what this means for estimating the size of earthquakes.
This line graph can reveal the temporal fluctuations in magnitude values for each magnitude type.
Each month shows similar patterns of a downward trend.
Extreme peaks and troughs
Body-wave, local and surface wave magnitudes start to fluctuate tremendously in the 1980s.
These scales all provide authorities with different insights in assessing the potential damage the seismic activities could bring.
Depth is the distance from the location of the earth where the earthquake originates and the surface of the earth.
As there are different types of earthquakes, namely shallow, intermediate or deep ones, relating them to the different magnitude types will provide the relevant authorities with insights on the energy release mechanisms, enabling them to further refine their models.
Most earthquakes tend to be shallower and quite a number of these events also have higher magnitudes than those events with a larger depth.
Logically speaking, shallower earthquakes are nearer to the earth’s surface and can have more intense impacts on the area. Therefore, shallow earthquakes with larger magnitudes are bound to cause more damage.
It is important to keep in mind that the magnitude value and depth of the earthquake can collectively determine the severity of the potential impact.
In conclusion, our analysis of earthquake events has provided valuable insights into the seismic activity in Turkey and its neighbouring countries. Through the static plots, interactive plots and gif animated plots, we have observed the frequency, spatial distribution and temporal trends of earthquakes in different locations, identified the trend of the earthquakes and average magnitude by year, and the correlation between frequency and average magnitude. Besides that, we were able to understand the nature of earthquake magnitudes by exploring and contrasting magnitude types in order to learn more about their features, variability and interconnections
The trend of earthquake frequency is increasing over time.
The trend of earthquake average magnitude and average depth is decreasing over time.
There is a negative correlation in the magnitude-frequency relationship, where smaller earthquakes occur more frequently than larger ones.
Akdeniz and Ege Denizi are the top two locations with the highest earthquake frequency.
The tectonic plate boundaries and fault lines influenced the magnitude and frequency of earthquakes.
The earthquake magnitudes are distributed lower for a few years after a big earthquake occurred.
Different pairs of magnitude types show different correlation coefficient values as they capture different aspects of an earthquake’s behaviour.
Each month of the year shows a similar pattern of downward trend in magnitude values for each magnitude type. However, there are tremendous fluctuations starting around the 1980s, most probably due to evolving seismic network and monitoring practices.
Most earthquakes tend to be shallower and quite a number of these occurrences have higher magnitudes than those occurrences with a larger depth.
Overall, the visualisations have deepened our understanding of earthquake occurrences. It is important to note that the advancement of modern technology continues to make the data collection process more accurate, thus improving decision making policies. Through this study, we found that it is important to be alert especially those who are in high-risk earthquake areas. Furthermore, the diverse visualisations presented by our group members have contributed to a comprehensive exploration of earthquake data, encompassing different perspectives and objectives.